1. Field of the Invention
The present invention relates to a method, program and apparatus for transfer or the like of electronic data via networks among information processors.
2. Description of the Related Art
In recent years, electronic data itself has become valuable and this electronic data has often been transferred. Electronic data includes, for example, music data such as MP3 data or the like, call termination melody data such as MIDI or the like, static image data such as JPEG data or the like, dynamic image data such as MPEG4 data or the like, and document data such as text data or the like (hereinafter referred to as “contents”).
If no problem occurs on a contract for transferring contents by recording the contents on a storage medium such as a CD-ROM (registered trademark) or the like, contents may be transferred by transferring the storage media or by transferring a code, or the like, indicating the right to use thereof.
However, a problem arises in the transfer, or the like, of contents provided through networks, in that contents are left at a transferor even when contents are transferred to a partner (purchaser). Therefore, for the transfer or the like of contents via such networks, it is required to transfer contents through a reliable system.
Japanese Patent Application Laid-open No. 2001-78266 discloses the conventional transfer or the like of contents among information processors via a network as a means for solving the problem described above.
An apparatus which serves as the transfer destination, obtains an encryption key for decoding of contents from a distribution server at the time the contents are transferred. The contents (e.g., encrypted music data) are distributed via a network to mobile phones from the distribution server. However, the contents are transferred among the mobile phones by recording the contents into memory cards.
However, the conventional means for transferring contents via the network cannot realize a transfer in a local environment such as where infrared rays are used, because the means is formed by three parties via the network. Moreover, such means has a disadvantage in that users may be concerned about reliability because exchanges of contents are administrated by a third party. In addition, the contents are transferred by recording into a memory card among the mobile phones, and the contents are not transferred via the network.